Revert "Lower the priority of Bluetooth mic even in wideband"

This reverts commit 21620925.

Reason for revert: The Bluetooth WBS feature has been enabled for 2+ releases and doing well. We think it's the good time to make BT mic auto selected instead of waiting for user to manually selecting it.

Bug: b/170388719

Original change's description:
> Lower the priority of Bluetooth mic even in wideband
>
> Bug: b/156333981
> Change-Id: Ieec9421a98119684f3ad901b16c1ad8dbe8998ef
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2196082
> Reviewed-by: Jenny Zhang <jennyz@chromium.org>
> Commit-Queue: Hsinyu Chao <hychao@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#772093}

TBR=hychao@chromium.org,jennyz@chromium.org,cychiang@chromium.org,yshavit@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: b/156333981
Change-Id: I855eb8f92c94d72f54379b4bdac15ff07c410c38
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2462901Reviewed-by: Hsinyu Chao <hychao@chromium.org>
Reviewed-by: Jenny Zhang <jennyz@chromium.org>
Commit-Queue: Hsinyu Chao <hychao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#816409}

chromeos/audio/audio_device.cc

@@ -18,19 +18,11 @@ namespace {
 // Get the priority for a particular device type. The priority returned
 // will be between 0 to 3, the higher number meaning a higher priority.
 uint8_t GetDevicePriority(AudioDeviceType type, bool is_input) {
-  // Lower the priority of bluetooth wide band mic. Although the quality is
-  // better than narrow band(AUDIO_TYPE_BLUETOOTH_NB_MIC), we still want
-  // to avoid auto-selecting Bluetooth mic when there is another audio input
-  // option.
-  if (type == AUDIO_TYPE_BLUETOOTH && is_input)
-    return 0;
   switch (type) {
     case AUDIO_TYPE_HEADPHONE:
     case AUDIO_TYPE_LINEOUT:
     case AUDIO_TYPE_MIC:
     case AUDIO_TYPE_USB:
-    // This is for bluetooth output node. Bluetooth inputs(wide band and narrow
-    // band mic) are handled separately.
     case AUDIO_TYPE_BLUETOOTH:
       return 3;
     case AUDIO_TYPE_HDMI: